The Brazilian scored in both halves for Lucien Favre's side as they climbed to fourth on the table with another home victory.
The signs were ominous for Braunschweig in the first 10 minutes, as the newly promoted outfit - who are yet to win a game this season - were lucky not to concede when Raffael missed two early chances.
Bayer Leverkusen loanee Karim Bellarabi fired wide for Braunschweig, and he looked a real threat, but Monchengladbach dominated the early play and claimed a deserved lead in the 22nd minute.
Swedish defender Oscar Wendt was the scorer, charging forward from left-back before cutting in and beating Braunschweig goalkeeper Marjan Petkovic with a right-footed effort from an acute angle inside the penalty area.
Raffael had a goal disallowed shortly after but he eventually opened his account in the 31st minute when he headed in Max Kruse's cross.
Bellarabi went close for the visitors shortly after the break before they pulled a goal back 13 minutes into the second half.
It was no surprise to see Bellarabi as the provider, with his cross from the right turned in by Mirko Boland.
Dominick Kumbela should have then equalised for Braunschweig but headed wide, and the hosts made them pay for their profligacy from the penalty spot.
Kruse was the scorer from 12 yards, before Raffael sealed Monchengladbach's win with a tap-in in the 76th minute.
Monchengladbach have now won all three of their home matches this season, but lost all three trips away.
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